Log turning assembly

ABSTRACT

A log turning assembly for rotating logs to be fed to a grinder magazine by a predetermined angle. The assembly comprises a conveyor for carrying the logs above the grinder magazine and a swivel box rotatably supported on a structure above the grinder magazine and below the conveyor. First gate means are located on the conveyor for dropping the logs in the swivel box, means are provided for turning the box by the predetermined angle when loading with logs, and a second gate means are located at the bottom of the swivel box for dropping the logs in the grinder magazine after rotation of the swivel box.

O Umted States Patent [191 [111 3,805,969 Bilocq Apr. 23, 1974 LOG TURNING ASSEMBLY Primary Examiner-Frank E. Werner [75] Inventor: Georges A. Bilocq, Plessisville, AtwmeyAgent or Flrm Raymond Roblc Quebec, Canada isfiiw V [73] Assignee: 22:21:: Limitee/Ltd., Quebec, [57] ABSTRACT [22] Filed: Feb. 8, 1973 A log turning assembly for rotating logs to be fed to a grinder magazine by a predetermined angle. The as- [211 Appl' 330723 sembly comprises a conveyor for carrying the logs above the grinder magazine and a swivel box rotatably [52] US. Cl. 214/1 R, 198/69, 198/33 R supported on a structure above the grinder magazine [51] Int. Cl. B65g 47/24 and below the conveyor. First gate means are located [58] Field of Search.....'.... 198/29, 69, 33 R, 33 AB; on the conveyor for dropping the logs in the swivel 193/43 R, 43 D; 214/1 Q, 1 R; 83/112 box, means are provided for turning the box by the predetermined angle when loading with logs, and a [56] References Cited second gate means are located at the bottom of the UNITED STATES PATENTS swivel box for dropping the logs in the grinder maga- 228 447 6/1880 Day et al 198/33 R zine after rotation of the swivel 3,100,039 8/l963 Oderman et al 198/33 AB 3,279,582 10/1966 Bilocq 198/33 AB 13 Claims, 7 Drawing Figures 'l My all I PATEN-TED APR 2 3 I974 SHEET 1 BF 4 PM'ENTED APR 23 m4 SHEET 2 [1F 4 LOG TURNING ASSEMBLY This invention relates to a log turning assembly for rotating logs to be fed to a grinder magazine by a prdetermined angle.

During installation of grinders in a pulp processing plant, it often happens that the space available for installing the grinders requires that such grinders be positioned so that the magazines are oriented at such an angle that the logs fed to such magazines, on conveyors are not in the right direction. Of course, the conveyors could be rearranged but this often disturbs the whole processing plant. Consequently, it is less expensive to provide log turning assemblies for turning the logs when they are unloaded from the conveyors.

It is therefore the object of the invention to provide a log turning assembly which is very simple and inexpensive.

The log turning assembly in accordance with the invention comprises a swivel box rotatably supported on a structure above the grinder magazine and below the conveyor. First gate means are located on the conveyor for dropping the logs in the swivel box and means are provided for turning the box by the angle required when loaded with logs. Finally, gate means are located at the bottom of the swivel box for dropping the los in the grinder magazine after rotation of the swivel box.

The structure supporting the swivel box includes a track and the box is provided with rollers for rotation on the track so as to permit the angle of movement of the box. The means for turning the box may include a pinion rotatably mounted on the structure, a chain secured to the box and adapted to mesh with the pinion a rack also meshed with the pinion, and means for operating the rack to cause the rotation of the pinion an the angular movement of the box.

The gates are opened and closed and the swivel box may be rotated by means of air pressure cylinders. Such air pressure cylinders are controlled by an electric circuit so as to sequentially open the first gate means to load logs in the swivel box, close the first gate means when the level of the logs in the swivel box has reached a predetermined height, turn the swivel box after the first gate means are closed, open the second gate means when the swivel box has reached its unloading position, close the second gate means when the swivel box is empty, and return the swivel box to its loading position when the second gate means are closed. The above operations may be done manually or automatically.

The invention will now be disclosed with reference to a preferred embodiment thereof and to the accompanying drawings in which:

FIG. 1 illustrates a perspective view of the log turning assembly in accordance with the invention:

FIG. 2 illustrates a side view of the log turning assembly of FIG. 1;

FIG. 3 illustrates a top view of the swivel box supporting structure;

FIGS. 4 and 5 illustrate the rotation of the swivel box by an angle of 90 and FIGS. 6 and 7 illustrate the electric circuit controlling the operation of the log turning assembly.

Referring to FIGS. 1 to 3, there is shown a portion of a conveyor including two gates 10 positioned between two end rollers 12 of conveyor belts 14. The gates are rotatably supported on the conveyor by shafts l6 and are operated by air pressure cylinder 18 secured to the conveyor and having a piston 20 secured to a lever 22 keyed on one of the shafts 16. The two gates are operated together by means of a lever 24 which is coupled to lever 22 and to another level 26 keyed to the other shaft 16. A limit switch LS is located adjacent one end of lever 24 so as to be actuated when the gates 10 are closed.

A structure is provided for supporting a swivel box 30 positioned right underneath gates 10. Such structure is composed of four columns 32 each having angle brackets 34 supporting a track 36. The swivel box 30 has rollers 38 mounted on each corner thereof and adapted to roll on track 36. The swivel box is rotated by means of a pinion 43 rotatably mounted on a transverse bar 42 located between two columns 32 and having a first gear meshing with a chain 44 secured to an arcuate bar 46 attached to swivel box 30. A second gear is provided on the pinion 47 and meshes with a rack 48 slidably mounted on transverse bar 42. The rack 48 is operated by an air pressure cylinder 50 secured to rack 48. Limit switches LS and LS are provided for detecting that the swivel box is in its loading and unloading position respectively. A photocell PC (not shown in FIG. l-3) is also provided for detecting the presence of wood in the swivel box whereas photocells PC and PC; are provided for detecting that the swivel box is full and half full respectively.

Two gates 56 are located at the bottom of the swivel box. Each gate is rotatably mounted on a shaft 58 and operated by an air pressure cylinder 60 having its piston 62 secured to a lever 64 keyed to shaft 58. Limit switches LS, and LShd 5 are provided for detecting that the gates 56 are closed. As illustrated in FIGS. 4 and 5, gates 56 are closed during rotation of the swivel box. The gates 56 are opened after rotation of the swivel box to unload the logs onto the grinder magazines not shown located right underneath the swivel box.

Referring now to FIGS. 6 an 7, there is shown the electrical circuit for operating the log turning assembly disclosed above. A suitable source of power such as 1 15 V, 60 Hz is applied to lines L and L through manual switch SW, and fuse F. When switch SW is closed, a pilot light PL will light up to indicate that the circuit is on. If the swivel box is empty, as should normally be the case, the photoelectric cell PC normally located at the bottom of the swivel box will detect the absence of logs and energize a second pilot light PL indicating that the swivel box is empty. A reset button RS is also provided for permitting to continue the cycle of operation of the machine following a loss of power or the opening of switch SW The operation of push button RS energizes relay RST and such relay will close contacts RST1 to lock itself and contacts RST-2 to power the circuit.

The operation of the log turning apparatus may be manual or automatic. If the operator desires to operate the apparatus manually, the switch SW is turned to the position MAN. If it is desired to operate the apparatus automatically the switch SW is turned to position AUTO.

In the position MAN, the gates 10 are opened to permit logs to fall onto the box by pressing button OP. If the limit switch LS is closed indicating that the swivel box is in its loading position and if limit switches LS, and LS are also closed indicating that both gates 56 of the swivel box are closed, a solenoid OPN will be energized through normally closed contacts R2-1 and T1-l. As it will be seen later, relay R operating contacts R2-1 is energized when the closed button CL is operated or when the swivel box is full. The contacts Tl-l are operated by timing relay T after a predetermined time interval to prevent the operator from mistakenly reopening the gates before turning the swivel box to its unloading position as it will be seen later. Solenoid OPN controls the cylinder 18 which operates the gates 10.

The pressing of button OP also energizes relay R and timing relay T Relay R and timing relay T lock themselves through contacts Rl-l of relay R and normally closed contacts R41 of a relay R, which opens its contacts only when the swivel box is rotated to its unloading position as it will be disclosed later. Following opening of the gates 10, the box will be loading with logs.

When the box is full, the operator presses on closed button CL to energize a solenoid CLS controlling the operation of the cylinder 18 for closing the gates 10. The pressing of button CL also operates pilot light P15 to indicate that the box is full and relay R to open contacts R2-l so as to deenergize solenoid OPN. It will also be noted that the relay R is also energized by photocells PC and PC when the swivel box is full.

When the gates are closed, the operator may press a button ROT to operate solenoid ROTI through normally open contacts R3-1 of relay R Relay R is closed when the gates 10 are closed thereby operating limit switch L5,. The energization of solenoid RO'IT controls the operation of cylinder 50 to rotate the swivel box 30.

The swivel box is then in its unloading position and a relay R is operated by the closure of limit switch LS which, as mentioned previously, is operated when the swivel box is in its unloading position. The unloading of the logs may be done by pressing buttons LF when only the left hand gate 56 is open, RG when only the right hand gate 56 is open or button BT when both gates 56 are open. The manual operation of the gates 56 will not be disclosed now because it is identical to the auto matic operation of the log turning assembly.

When it is desired'to return the swivel box to its loading position after unloading of the logs, the return button RET is pressed by the operator for energizing solenoid RETN which controls cylinder 50.

If the operator chooses to operate the apparatus automatically, switch SW is moved to position AUTO. The automatic opening of the gates will be initiated by the pressing of button LD instead of button OP. Solenoid OPN and relays R and T are thus operated in the same manner as for the manual operation. A timing relay T is provided for permitting the swivel box 30 to fill to its full capacity. Such timing relay T is energized through normally closed contacts R3-2 of a relay R which is deenergized when the gates 10 are open because limit switch LS is open. When the timing period of relay T has lapsed, contacts T2-2 are closed to cause energization of solenoid CLS to close the gates 10 if the level of the logs in the swivel box has exceeded the half full mark controlled by photocell PC The light PL and the relay R will also be energized. The energization of relay R will close contacts R2-l to release solenoid OPN. It will also benoted that the solenoid CLS, the pilot light PL and the relay R may also be operated by photocell PC when the swivel box becomes full before the end of the timing period of timing relay T The energization of relay R also closes contacts R2-2 to energize relay R to normally close contacts R42 of relay R As it will be seen later, relay R is not energized until the swivel box 30 has moved to its unloading position. Relay R locks itself operated through its own contacts R5l and energizes timing relay T through its other contacts R5-2. After a predetermined timing interval, timing relay T closes its contacts T3-1 to energize solenoid RO'IT to rotate the swivel box 30. The timing period of timing relay T is chosen so as to insure that the gates 10 will be closed before the swivel box 30 starts to rotate.

The unloading of the box is initiated by the operator in the manual and automatic operation of the apparatus. To open the left hand gate, button LP is closed to energize relay R through now closed contacts R4-4 of relay R As mentioned previously, relay R is energized through limit switch LS when the swivel box has moved to its unloading position. The energization of relay R closes contacts R6-l to operate timing relay T and relay R The timing relay T and the relay R lock themselves through their own contacts T6-l and RIO-1 connected in series. The operation of relay R closes contacts R10-2 to energize solenoid HDLF which releases the pressure on the cylinder controlling th operation of left gate 56. The closure of contacts RIO-2 also energizes relay R through normally closed contacts R62 of timing'relay T The energization of relay R closes contacts Rl2-1 to operate solenoid OPLT controlling the operation of cylinder 60 to open left gate 56. The timing period of timing relay T is adjusted so that its contacts T6-l and T6-2 are operated shortly after solenoid HDLF and OPLF are energized so as to impart a high pressure on the cylinders at the beginning of the opening of the gates only. There is no pressure applied on the cylinders towards the end of the opening of the gates so as to prevent slamming of the gates at the end of their travel.

When the operator releases the button LF, relay R is released and timing relay T and relay R will be energized though then closed contacts T6-3, normally closed contacts R9-1, normally closed contacts R6-2 and normally closed contacts R7-l. The function of relays R-, and R will be disclosed later. The timing relay T and relay R lock themselves operated through normally closed contacts T7-1 and then closed contacts R1 1-1. The energization of relay R also closes contacts R1l-2 to energize solenoid CLLf to close the left gate 56. After the expiration of the timing period of timing relay T contacts T7-2 will be opened to release relay R and timing relay T so as to reset such relays. The contacts T7-1 of timing relay T will also be opened to release relay R and timing relay T The three solenoids are then released and the whole pressure is applied on the left gate cylinder to hold the gate closed.

When the operator wishes to open the right gate 56, the button RG is pushed to close the circuit of relay R The operation of relay R closes contacts R8-1 to energize timing relay T and relay R The timing relay T and the relay R lock themselves operated through their own contacts T8-1 and Rl3-l connected in series. Relay R closes contacts R13-2 to energize solenoid HDRG which releases the pressure on the cylinder 60 controlling the operation of the right gate 56. The closure of contacts R13-2 also energizes relay R through normally closed contacts T8-2 of timing relay T The energization of relay R closes contacts Rl5-1 to operate solenoid OPRG controlling the operation of cylinder 60 to open right gate 56. The timing period of timing relay T is adjusted so that its contacts T8-l and T8-2 are operated shortly after the solenoids HDRG and OPRG are energized so as to impart a high pressure on the cylinders at the beginning of the opening of the gates only. There is no pressure on the cylinders at the end of the opening of the gates so as to prevent slamming of gates.

When the operator releases the button RG when the swivel box is empty, relay R is deenergized to close contacts R8-2 and timing relay T and relay R will be energized through then closed contacts T83 and normally closed contacts R9-2 and R7-2. The timing relay T and relay l4 lock themselves operated through their contacts T9-l and Rl4-1. The operation of relay R closes contacts R14-2 to energize solenoid CLRG to close right hand gate 56. After the expiration of the timing period of timing relay T contacts T9-2 will be opened to release relay R and timing relay T so as to reset such relays. The contacts T9-l of timing relay T will open to release relay R after a predetermined timing period to release itself and relay R THe three solenoids are then released and the whole pressure is reapplied on the cylinder controlling the right gate to hold the gate closed.

When the operator desires to operate both gates at the same time, he pushes button BT to energize relay R The energization of relay R closes contacts R7-3 and R74 to initiate the opening of both gates together. When push button BT is released, relay R is released to close both gates in the manner disclosed above for the left and right gates.

The automatic opening and closing of gates 56 is initiated by timing relay T and relay R which are energized through normally closed contacts T5-2 of timing relay T switch SW which is closed when the swivel box is loaded and through contacts R4-3 of relay R which is operated when the swivel box 30 is in its unloading position. After its timing period has elapsed (time necessary to stop the swivel box at its unloading position) relay T closes its contacts T4-l and T4-2 to initiate opening of both gates 56 in the same manner as disclosed above. When the timing period of timing relay T has ended, contacts TS-Z open to release timing relay T and relay R and thus close the gates and bring the circuit back to its rest position.

Relay R is used to prevent the gates 56 from closing when contacts T63 are closed until thetiming period of T has ended.

Contacts R7-l and R7-2 which are positioned in the energizing circuit of timing relay T and relay R on one hand and timing relay T and relay R on the other hand are provided to maintain the left or right gate 56 opened if the operator, after having pressed button LP or button RG decides to open both gates by pressing button BT even if he releases buttons LF and RG. Contacts R7-1 or R7-2 will then open to prevent energization of the relays associated with the closure of the gates 56.

After the timing period of timing relay T has elapsed, contacts T5-l are closed and solenoid RETN is energized to control the operation of cylinder 50 which brings the swivel box back to its loading position.

Although the invention has been disclosed with reference to a preferred embodiment thereof, it is to be understood that various modifications may be made thereto and that the scope of the invention is to be limited by the claims only.

I claim:

1. A log turning assembly for rotating logs to be fed into a grinder magazine by a predetermined angle comprising:

a. a conveyor for carrying the logs above the grindermagazine;

b. a swivel box rotatably supported on a structure above the grinder magazine and below said conveyor;

c. first gate means located in said conveyor for dropping logs in said swivel box;

(1. means for turning the box by said predetermined angle when loaded with logs; and

e. second gate means located at the bottom of said swivel box for dropping the logs in the grinder magazine after rotation of the swivel box.

2. A log turning assembly as defined in claim 1, in-

cluding air pressure cylinders for opening and closing the first and second gates.

3. A log turning assembly as defined in claim 1, wherein said structure includes an annular track and wherein rollers are mounted on said box for rotation on said track so as to permit angular movement of said box by said predetermined angle.

4. A log turning assembly as defined in claim 2, wherein the means for turning the box include a pinion rotatably mounted on said structure, a chain secured to said box and adapted to mesh with said pinion, a rack also meshing with said pinion, and means for operating said rack to cause rotation of the pinion and the angular movement of the box.

5. A log turning assembly as defined in claim 4, wherein said means for operating said rack is an air pressure cylinder.

6. A log turning assembly as defined in claim 5, further comprising an electric circuit for controlling the operation of said air pressure cylinders so as to sequentially operate the first gate means to load logs in the swivel box, close the first gate means when the level of the logs in the swivel box has reached a predetermined height, turn the swivel box after the first gate means are closed, open the second gate means when the swivel box has reached its unloading position, close said second gate means when the swivel box is empty, and return the swivel box to its loading position when the second gate means are closed.

7. A log turning assembly as defined in claim 6, wherein said electric circuit includes solenoids for operating said cylinders and wherein the sequential operation of said solenoids is controlled manually.

8. A log turning assembly as defined in claim 7, wherein a limit switch is provided for preventing rotation of the swivel box before the first gate means are closed.

9. A log turning assembly as defined in claim 7, wherein timing relays are provided for controlling the time necessary for opening and closing the second gate means.

wherein said electric circuit includes solenoids for operating said cylinders, and wherein the sequential operation is controlled automatically.

13. A log turning assembly as defined in claim 12, wherein limit switches, photocells and timing relays are provided for controlling the sequential operation. 

1. A log turning assembly for rotating logs to be fed into a grinder magazine by a predetermined angle comprising: a. a conveyor for carrying the logs above the grinder magazine; b. a swivel box rotatably supported on a structure above the grinder magazine and below said conveyor; c. first gate means located in said conveyor for dropping logs in said swivel box; d. means for turning the box by said predetermined angle when loaded with logs; and e. second gate means located at the bottom of said swivel box for dropping the logs in the grinder magazine after rotation of the swivel box.
 2. A log turning assembly as defined in claim 1, including air pressure cylinders for opening and closing the first and second gates.
 3. A log turning assembly as defined in claim 1, wherein said structure includes an annular track and wherein rollers are mounted on said box for rotation on said track so as to permit angular movement of said box by said predetermined angle.
 4. A log turning assembly as defined in claim 2, wherein the means for turning the box include a pinion rotatably mounted on said structure, a chain secured to said box and adapted to mesh with said pinion, a rack also meshing with said pinion, and means for operating said rack to cause rotation of the pinion and the angular movement of the box.
 5. A log turning assembly as defined in claim 4, wherein said means for operating said rack is an air pressure cylinder.
 6. A log turning assembly as defined in claim 5, further comprising an electric circuit for controlling the operation of said air pressure cylinders so as to sequentially operate the first gate means to load logs in the swivel box, close the first gate means when the level of the logs in the swivel box has reached a predetermined height, turn the swivel box after the first gate means are closed, open the second gate means when the swivel box has reached its unloading position, close said second gate means when the swivel box is empty, and return the swivel box to its loading position when the second gate means are closed.
 7. A log turning assembly as defined in claim 6, wherein said electric circuit includes solenoids for operating said cylinders and wherein the sequential operation of said solenoids is controlled manually.
 8. A log turning assembly as defined in claim 7, wherein a limit switch is provided for preventing rotation of the swivel box before the first gate means are closed.
 9. A log turning assembly as defined in claim 7, wherein timing relays are provided for controlling the time necessary for opening and closing the second gate means.
 10. A log turning assembly as defined in claim 9, wherein said second gate means includes two separate gates which may be operated separately or together.
 11. A log turning assembly as defined in claim 7, wherein a timing relay is provided for preventing reopening of said first gate means before the swivel box has gone to its unloading position.
 12. A log turning assembly as defined in claim 6, wherein said electric circuit includes solenoids for operating said cylinders, and wherein the sequential operation is controlled automatically.
 13. A log turning assembly as defined in claim 12, wherein limit switches, photocells and timing relays are provided for controlling the sequential operation. 